This application relates generally to wire matrix printers, and more particularly to a compact, rapid and economical arrangement of print wires and electromagnetic actuating mechanisms for a matrix printer. The application also relates to certain features of electromagnetic actuator mechanisms, generally, having particular utility in the selective operation of print wires such as are used in matrix printers.
Matrix printers of many styles have been known in the art for a great many years. Typical, generally related printers are disclosed in P. A. Brumbaugh et al. U.S. Pat. No. 3,672,482; A. S. Chou et al. U.S. Pat. No. 3,592,311; E. D. Finnegan U.S. Pat. No. 3,627,096; R. S. Bradshaw U.S. Pat. No. 3,217,640; W. Wockenfuss et al. U.S. Pat. No. 2,683,410; and K. A. Knutsen U.S. Pat. No. 2,869,455; all herein incorporated by reference. In various ones of such printers, a vertical column of spaced print wires is mounted on a carriage and traversed across a paper. In a typical example, using a 5 .times. 7 dot matrix for the characters, a column of seven print wires travels across the paper five steps or printing columns to the complete character. At each possible printing column, selected ones of the seven print wires (from zero to all seven) are actuated or "fired" to drive the printing ends of the selected wires against an inked ribbon and paper in a printing pattern, based on which wires were actuated; or the selected wires otherwise mark the record medium in any known fashion.
This invention, generally, seeks to improve such matrix printers by providing a very light, compact and inexpensive print head and print wire layout, particularly one with essentially straight, parallel print wires, and by providing a very small, efficient and extremely rapid electromagnetic actuating structure for operating such print wires. The invention also is concerned with new and improved electromagnetic actuator mechanisms having generally utility, and especially useful in selectively actuating an array of closely spaced, essentially parallel workpieces, such as the print wires of a matrix printer.
The invention is also concerned with improved electromagnetic actuator structures of the general class disclosed in W. J. Zenner U.S. Pat. No. 3,056,546, herein incorporated by reference. The Zenner patent relates to a punch system including a combination of a spring reed and an electromagnet for operating the reed to selectively cock and fire the reed and associated punch element. The present invention relates to improved actuators of the Zenner type that are small and compact, and low in electrical power consumption. The invention further concerns pole face and armature construction, geometry, and circuit operating principles for such electromagnetic actuators, particularly using a thin flat assembly of magnet cores and armatures. Further, the invention relates to improved flexible couplings for mounting a workpiece, such as a print wire, to a spring-reed actuator such as is disclosed in the Zenner patent.